Moringa extracts used in sugarcane juice treatment and effects on ethanolic fermentation

The objective of this study was to evaluate the effects of sugarcane juice treatment using Moringa oleifera leaf and seeds extracts on ethanolic fermentation. The experiment was arranged in a split plot statistical design, with four replications. Main treatments were three sedimentation agents (synthetic polyelectrolyte, moringa leaf and seed extracts) and control while the secondary treatments were two sugarcane varieties (RB867515 and CTC4). Extracted sugarcane juice was clarified by simple defecation with pH adjusted to 6.0. The flocculating agents were added in a decanter before the limed juice. After then, the juice was standardized to 16° Brix at pH 4.5, and musts were inoculated with yeast Saccharomyces cerevisiae strain, FT858. At the end of the fermentation process, wines were recovered by centrifugation. In all experimental stages, extracted juice, clarified juice and wine were chemically and technologically characterized. The use of moringa leaf and seed extracts as sedimentation adjuvants did not increase the sedimentation speed of impurities. However, there was a high sludge compaction, which was essential for maintenance of yeast and bud population at the beginning of fermentation, and yeast budding rate in the end. The use of different sedimentation agents as adjuvants in juice treatment did not affect wine quality and ethanol yield.

Ethanol production using hemicellulosic hydrolyzate and sugarcane juice with yeasts that converte pentoses and hexoses

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Carotenoid production by Rhodotorula rubra cultivated in sugarcane juice, molasses, and syrup

A produção de biomassa e de carotenoides por Rhodotorula rubra foi estudada em meios à base de caldo, melaço e xarope de cana. Avaliou-se o efeito da suplementação dos meios com nitrogênio na forma de ureia ou do nutriente comercial Nitrofos KL. O delineamento experimental utilizado foi o inteiramente casualizado, no esquema fatorial 3 × 3, sendo um dos fatores o substrato (caldo, melaço e xarope) e o outro a suplementação (controle, ureia e Nitrofos KL). Os resultados foram submetidos à análise de variância e teste de Tukey a 5% de probabilidade. As maiores produções de massa seca de levedura foram obtidas no meio à base de melaço suplementado com ureia ou Nitrofos KL (15,09 e 14,87 g/L, respectivamente). A produção de carotenoides intracelular foi elevada em todos os meios estudados sem suplementação (0,329 mg/g). Para a produção volumétrica, o melhor meio foi o melaço (2,74 mg/L), enquanto a suplementação com ureia e com Nitrofos KL produziu 2,55 e 2,32 mg/L, respectivamente. Os principais carotenoides produzidos foram toruleno, torularrodina e β-caroteno. No meio à base de caldo de cana sem suplementação, houve o menor consumo de carboidratos, enquanto que o meio com suplementação à base de ureia obteve o maior consumo.

GROWTH AND FERMENTATION CHARACTERISTICS OF NEW SELECTED STRAINS OF SACCHAROMYCES AT HIGH-TEMPERATURES AND HIGH CELL DENSITIES

Maintenance of high cell viability was the main characteristic of our new strains of thermotolerant Saccharomyces. Total sugar conversion to ethanol was observed for sugarcane juice fermentation at 38-40-degrees-C in less than 10 h and without continuous aeration of the culture. Invertase activity differed among the selected strains and increased during fermentation but was not dependent on cell viability. Invertase activity of the cells and optimum temperature for growth, as well as velocity of ethanol formation, were dependent on medium composition and the type of strain used. At high sugarcane syrup concentrations, the best temperature for ethanol formation by strain 781 was 35-degrees-C. Distinct differences among the velocities of ethanol production using selected strains were also observed in sugarcane syrup at 35-38-degrees-C.

Rheology and fluid dynamics properties of sugarcane juice

The sugarcane juice is a relatively low-cost agricultural resource, abundant in South Asia, Central America and Brazil, with vast applications in producing ethanol biofuel. In that way, a good knowledge of the rheological properties of this raw material is of crucial importance when designing and optimizing unit operations involved in its processing. In this work, the rheological behavior of untreated (USCJ, 17.9 °Brix), clarified (CSCJ, 18.2 °Brix) and mixed (MSCJ, 18.0 °Brix) sugarcane juices was studied at the temperature range from 277K to 373K, using a cone-and-plate viscometer. These fluids were found to present a Newtonian behavior and their flow curves were well-fitted by the viscosity Newtonian model. Viscosity values lied within the range 5.0×10 -3Pas to 0.04×10 -3Pas in the considered temperature interval. The dependence of the viscosity on the temperature was also successfully modeled through an Arrhenius-type equation. In addition to the dynamic viscosity, experimental values of pressure loss in tube flow were used to calculate friction factors. The good agreement between predicted and measured values confirmed the reliability of the proposed equations for describing the flow behavior of the clarified and untreated sugarcane juices. © 2010 Elsevier B.V.

Use of Moringa oleífera Lamarck leaf extract as sugarcane juice clarifier: effects on clarifed juice and sugar

The objective of this study was to evaluate the effect of Moringa oleifera Lam. leaf extract on the sedimentation of impurities in the treatment of sugarcane juice and the effects on sugar quality and on the clarified juice. The experimental design used was a 4x2 factorial arrangement with four replications. The main treatments performed included the extracted original sugarcane juice, the synthetic polyelectrolyte (Flomex 9076), the leaf extract, and a control. The secondary treatments consisted of the sugarcane varieties RB92579 and RB867515. The clarification process used was simple defecation, in which the flocculating agents and the juice, limed and heated, were poured simultaneously into a decanter. The microbiological and chemico-technological characteristics of the extracted and clarified juices were evaluated. The clarified juice was concentrated up to 60° Brix (syrup) and subjected to boiling in a pilot pan using seeds to perform the graining: The sugar was recovered by centrifugation and analyzed for microbiological and chemico-technological characteristics. It was concluded that the use of the Moringa oleifera Lam. leaves extract resulted in a better quality of clarified juice and sugar.

Spittlebug infestation in sugarcane affects ethanolic fermentation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mathematical modeling of a continuous alcoholic fermentation process in a two-stage tower reactor cascade with flocculating yeast recycle

Experiments of continuous alcoholic fermentation of sugarcane juice with flocculating yeast recycle were conducted in a system of two 0.22-L tower bioreactors in series, operated at a range of dilution rates (D (1) = D (2) = 0.27-0.95 h(-1)), constant recycle ratio (alpha = F (R) /F = 4.0) and a sugar concentration in the feed stream (S (0)) around 150 g/L. The data obtained in these experimental conditions were used to adjust the parameters of a mathematical model previously developed for the single-stage process. This model considers each of the tower bioreactors as a perfectly mixed continuous reactor and the kinetics of cell growth and product formation takes into account the limitation by substrate and the inhibition by ethanol and biomass, as well as the substrate consumption for cellular maintenance. The model predictions agreed satisfactorily with the measurements taken in both stages of the cascade. The major differences with respect to the kinetic parameters previously estimated for a single-stage system were observed for the maximum specific growth rate, for the inhibition constants of cell growth and for the specific rate of substrate consumption for cell maintenance. Mathematical models were validated and used to simulate alternative operating conditions as well as to analyze the performance of the two-stage process against that of the single-stage process.

Yeast CA-11 fermentation in musts treated with brown and green propolis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influence of Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) injury on the quality of cane juice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Uso de caldo de cana-de-açúcar para produção de levana por Zymomonas mobilis CCT4494

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Friction factors, convective heat transfer coefficients and the Colburn analogy for industrial sugarcane juices

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bioethanol - Brazil, 30 years of Proálcool

Brazil, which has always been in the forefront of sugarcane production, also occupies a prominent position as the first country to produce and use biofuel in its automobile fleet. This fact is a consequence of the introduction of a program which has already turned 30 years, the Próalcool (National Alcohol Program). The oil crisis in the seventies encouraged the government to develop an alternative way to replace gasoline. Bioethanol was then born as fuel obtained from fermentation of sugarcane juice, molasses or both. In the eighties, 85% of the cars ran exclusively on alcohol. Ethanol production in that decade exceeded sugarcane production by the mills. The installed units reached in that period the capacity to produce 18 billion liters of bioethanol per season, a volume equivalent to 100 million barrels of gasoline. The fermentation process, which so far had been restricted to manufacturing sugarcane liquor (aguardente) or ethanol as a byproduct of sugarcane, takes over the spotlight in the entrepreneurial scene. As a result, processes comprising engineering concepts came up and most of the biological phenomena involved in fermentation were understood. The knowledge gathered and the units installed have granted Brazil the hold of production technology and use of a clean fuel.

L(+) Lactic acid production by new Lactobacillus rhamnosus B 103

L(+) Lactic acid fermentation was studied by Lactobacillus rhamnosus sp. under the effects of pH control and a lowcost nutritional medium (sugarcane juice and corn steep liquor-CSL). Central composite design (CCD) was employed to determine maximum lactic acid production at optimum values for process variables and a satisfactory fit model was realized. Statistical analysis of the results showed that the linear and quadratic terms of two variables (sugarcane juice and pH) had significant effects. The interactions between the three variables were found to contribute to the response at a significant level. A second-order polynomial regression model estimated that the maximum lactic acid production of 86.36 g/L was obtained when the optimum values of sucrose, CSL and pH were 112.65 g/L, 29.88 g/L and 6.2, respectively. Verification of the optimization showed that L(+) lactic acid production was of 85.06 g/L. Under these conditions, Y P/S and Q P values of 0.85 g/g and 1.77 g/Lh, respectively, were obtained after 48 h fermentation, with a maximal productivity of 2.2 g/L h at 30 h of process. © 2010 de Lima CJB, et al.

Anaerobic digestion of stillage to produce bioenergy in the sugarcane-to-ethanol industry

Stillage is the main wastewater from ethanol production, containing a high chemical oxygen demand in addition to acidic and corrosive characteristics. Though stillage may be used as a soil fertilizer, its land application may be considered problematic due its high polluting potential. Anaerobic digestion represents an effective alternative treatment to reduce the pollution load of stillage. In addition, the methane gas produced within the process may be converted to energy, which can be directly applied to the treatment plant. The objective of this paper was to investigate the energetic potential of anaerobic digestion applied to stillage in the sugarcane ethanol industry. An overall analysis of the results indicates energy recovery capacity (ERC) values for methane ranging from 3.5% to 10%, respectively, for sugarcane juice and molasses. The processes employed to obtain the fermentable broth, as well as the distillation step, represent the main limiting factors to the energetic potential feasibility. Considering financial aspects the annual savings could reach up to US$ 30 million due to anaerobic digestion of stillage in relatively large-scale distilleries (365,000 m3 of ethanol per year). The best scenarios were verified for the association between anaerobic digestion of stillage and combustion of bagasse. In this case, the fossil fuels consumption in distilleries could be fully ceased, such the ERC of methane could reach values ranging from 140% to 890%. © 2013 Taylor & Francis.